codysnider / tt-rss

classes/feedparser.php

<?php
class FeedParser {
    private $doc;
    private $error;
    private $libxml_errors = array();
    private $items;
    private $link;
    private $title;
    private $type;
    private $xpath;

    const FEED_RDF = 0;
    const FEED_RSS = 1;
    const FEED_ATOM = 2;

    public function __construct($data) {
        libxml_use_internal_errors(true);
        libxml_clear_errors();
        $this->doc = new DOMDocument();
        $this->doc->loadXML($data);

        mb_substitute_character("none");

        $error = libxml_get_last_error();

        if ($error) {

$error is of type LibXMLError, thus it always evaluated to true.

            foreach (libxml_get_errors() as $error) {
                if ($error->level == LIBXML_ERR_FATAL) {
                    if (!isset($this->error)) {
                        //currently only the first error is reported
                        $this->error = $this->format_error($error);
                    }
                    $this->libxml_errors [] = $this->format_error($error);
                }
            }
        }
        libxml_clear_errors();

        $this->items = array();
    }

    public function init() {
        $xpath = new DOMXPath($this->doc);
        $xpath->registerNamespace('atom', 'http://www.w3.org/2005/Atom');
        $xpath->registerNamespace('atom03', 'http://purl.org/atom/ns#');
        $xpath->registerNamespace('media', 'http://search.yahoo.com/mrss/');
        $xpath->registerNamespace('rdf', 'http://www.w3.org/1999/02/22-rdf-syntax-ns#');
        $xpath->registerNamespace('slash', 'http://purl.org/rss/1.0/modules/slash/');
        $xpath->registerNamespace('dc', 'http://purl.org/dc/elements/1.1/');
        $xpath->registerNamespace('content', 'http://purl.org/rss/1.0/modules/content/');
        $xpath->registerNamespace('thread', 'http://purl.org/syndication/thread/1.0');

        $this->xpath = $xpath;

        $root = $xpath->query("(//atom03:feed|//atom:feed|//channel|//rdf:rdf|//rdf:RDF)");

        if ($root && $root->length > 0) {
            $root = $root->item(0);

            if ($root) {
                switch (mb_strtolower($root->tagName)) {
                case "rdf:rdf":
                    $this->type = $this::FEED_RDF;
                    break;
                case "channel":
                    $this->type = $this::FEED_RSS;
                    break;
                case "feed":
                case "atom:feed":
                    $this->type = $this::FEED_ATOM;
                    break;
                default:
                    if (!isset($this->error)) {
                        $this->error = "Unknown/unsupported feed type";
                    }
                    return;
                }
            }

            switch ($this->type) {
            case $this::FEED_ATOM:

                $title = $xpath->query("//atom:feed/atom:title")->item(0);

                if (!$title) {
                                    $title = $xpath->query("//atom03:feed/atom03:title")->item(0);
                }


                if ($title) {
                    $this->title = $title->nodeValue;
                }

                $link = $xpath->query("//atom:feed/atom:link[not(@rel)]")->item(0);

                if (!$link) {
                                    $link = $xpath->query("//atom:feed/atom:link[@rel='alternate']")->item(0);
                }

                if (!$link) {
                                    $link = $xpath->query("//atom03:feed/atom03:link[not(@rel)]")->item(0);
                }

                if (!$link) {
                                    $link = $xpath->query("//atom03:feed/atom03:link[@rel='alternate']")->item(0);
                }

                if ($link && $link->hasAttributes()) {
                    $this->link = $link->getAttribute("href");
                }

                $articles = $xpath->query("//atom:entry");

                if (!$articles || $articles->length == 0) {
                                    $articles = $xpath->query("//atom03:entry");
                }

                foreach ($articles as $article) {
                    array_push($this->items, new FeedItem_Atom($article, $this->doc, $this->xpath));
                }

                break;
            case $this::FEED_RSS:
                $title = $xpath->query("//channel/title")->item(0);

                if ($title) {
                    $this->title = $title->nodeValue;
                }

                $link = $xpath->query("//channel/link")->item(0);

                if ($link) {
                    if ($link->getAttribute("href")) {
                                            $this->link = $link->getAttribute("href");
                    } else if ($link->nodeValue) {
                                            $this->link = $link->nodeValue;
                    }
                }

                $articles = $xpath->query("//channel/item");

                foreach ($articles as $article) {
                    array_push($this->items, new FeedItem_RSS($article, $this->doc, $this->xpath));
                }

                break;
            case $this::FEED_RDF:
                $xpath->registerNamespace('rssfake', 'http://purl.org/rss/1.0/');

                $title = $xpath->query("//rssfake:channel/rssfake:title")->item(0);

                if ($title) {
                    $this->title = $title->nodeValue;
                }

                $link = $xpath->query("//rssfake:channel/rssfake:link")->item(0);

                if ($link) {
                    $this->link = $link->nodeValue;
                }

                $articles = $xpath->query("//rssfake:item");

                foreach ($articles as $article) {
                    array_push($this->items, new FeedItem_RSS($article, $this->doc, $this->xpath));
                }

                break;

            }

            if ($this->title) {
                $this->title = trim($this->title);
            }
            if ($this->link) {
                $this->link = trim($this->link);
            }

        } else {
            if (!isset($this->error)) {
                $this->error = "Unknown/unsupported feed type";
            }
            return;
        }
    }

    public function format_error($error) {
        if ($error) {
            return sprintf("LibXML error %s at line %d (column %d): %s",
                $error->code, $error->line, $error->column,
                $error->message);
        } else {
            return "";
        }
    }

    // libxml may have invalid unicode data in error messages
    public function error() {
        return UConverter::transcode($this->error, 'UTF-8', 'UTF-8');
    }

    // WARNING: may return invalid unicode data
    public function errors() {
        return $this->libxml_errors;
    }

    public function get_link() {
        return clean($this->link);
    }

    public function get_title() {
        return clean($this->title);
    }

    public function get_items() {
        return $this->items;
    }

    public function get_links($rel) {
        $rv = array();

        switch ($this->type) {
        case $this::FEED_ATOM:
            $links = $this->xpath->query("//atom:feed/atom:link");

            foreach ($links as $link) {
                if (!$rel || $link->hasAttribute('rel') && $link->getAttribute('rel') == $rel) {
                    array_push($rv, clean(trim($link->getAttribute('href'))));
                }
            }
            break;
        case $this::FEED_RSS:
            $links = $this->xpath->query("//atom:link");

            foreach ($links as $link) {
                if (!$rel || $link->hasAttribute('rel') && $link->getAttribute('rel') == $rel) {
                    array_push($rv, clean(trim($link->getAttribute('href'))));
                }
            }
            break;
        }

        return $rv;
    }
}